The present invention relates to medical bandage products. In particular, this invention relates to an orthopedic splinting product and a casting product, both utilizing a nonwoven substrate that can be used to stabilize a fracture or sprain or any other injury that requires a rigid or semi-rigid support.
Medical bandages for use in the treatment of injuries, such as broken bones requiring immobilization of a body member, are generally formed from a strip of fabric or scrim material impregnated with a substance which hardens into a rigid structure after the strip has been wrapped around the body member.
Conventional practice has been to fabricate a cast or splint upon an injured limb by initially applying to the limb a protective covering of a cotton fabric or the like, and then overwrapping the covering and limb with a substrate impregnated with plaster-of-paris or a substrate formed from flexible fiberglass fabric layers impregnated with a moisture-curable resin. Casts or splints formed from these materials possess several disadvantages. In particular, casts or splints formed using plaster-of-paris impregnated substrates have a relatively low strength to weight ratio. This results in a finished cast or splint that is very heavy and bulky. Furthermore, plaster-of-paris casts or splints are slow to harden, requiring 24 to 72 hours to reach maximum strength. Because plaster-of-paris breaks down in water, bathing and showering are difficult. Even if wetting due to these causes can be avoided, perspiration over an extended period of time can break down the plaster-of-paris and create a significant problem with odor and itching.
Casts or splints utilizing moisture-curable substrates formed from fiberglass fabric layers are lighter, waterproof and much stronger. However, cured casts or splints made using such substrates can become brittle, break down during wear which can lead to them being replaced. Furthermore, fiberglass is a composition that is highly irritating to mammalian skin.
In order to alleviate the above-recited disadvantages of the conventional cast or splint utilizing plaster-of-paris impregnated substrates and moisture-curable resin impregnated fiberglass substrates, resin-impregnated non-glass substrates formed from a knitted or woven fabric have been devised. The knitted fabric substrate provides a cast or splint that exhibits good conformability, possesses sufficient rigidity when cured, and shows no loss of strength. However, casting and splinting products incorporating knitted fabric substrates require a knitting process that is often expensive and time consuming. Additionally, casts and splints formed using a knitted fabric substrate can result in non-uniform and rough edges that are uncomfortable to the patient.
The present invention overcomes the disadvantages of the prior art by providing a substrate that does not irritate skin and is simple and inexpensive to manufacture.